Le Zhou

Northwest University, Northwest Harborcreek, Pennsylvania, United States

Are you Le Zhou?

Claim your profile

Publications (40)96.89 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: A new coordination polymer, [Cu3(dtb)(CN)3]n (1) (dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene) based on Cu3(CN)2 clusters, has been synthesized under solvothermal conditions, and characterized by elemental analysis, infrared spectrometry, powder X-ray diffraction, thermogravimetric analysis, and single-crystal X-ray diffraction. Complex 1 exhibits a three-dimensional twofold interpenetrated net with 6-connected uninodal topology. Moreover, solid state luminescent property of 1 has been investigated at room temperature.
    Journal of Cluster Science 02/2014; · 1.11 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Five new (4-8) and three known (1-3) dihydro-β-agarofuran sesquiterpene polyesters were isolated from the whole plants of Parnassia wightiana. The structures of all compounds were elucidated through spectroscopic analysis including 2D-NMR and HR-MS. The absolute configuration of these compounds was established by X-ray diffraction analysis, comparison of NOESY spectra and biogenetic means. The cytotoxities of compounds 2-8 were evaluated in vitro against HL-60, SMMC-7721, A549, MCF-7 and SW480 cell lines. Compounds 5-7 exhibited the highest activities with IC50 values of 11.8-30.1 μM in most cases. The SAR revealed that the introduction of hydroxyl group was able to significantly improve the activities of the compounds for most of the cell lines.
    International Journal of Molecular Sciences 01/2014; 15(6):11111-11125. · 2.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: As part of our continuing research on isoquinoline acaricidal drugs, this paper reports the preparation of a series of the 2-aryl-1-cyano-1,2,3,4-tetrahydroisoquinolines with various substituents on the N-phenyl ring, their in vitro acaricidal activities against Psoroptes cuniculi, a mange mite, and discusses their SAR as well. The structures of all compounds, including 12 new ones, were elucidated by analysis of UV, IR, NMR, ESI-MS, HR-MS spectra and X-ray diffraction experiments. All target compounds showed varying degrees of activity at 0.4 mg/mL. Compound 1 showed the strongest activity, with a 50% lethal concentration value (LC50) of 0.2421 μg/mL and 50% lethal time value (LT50) of 7.79 h, comparable to the standard drug ivermectin (LC50 = 0.2474 μg/mL; LT50 = 20.9 h). The SAR showed that the substitution pattern on the N-aromatic ring exerted a significant effect on the activity. The substituents 2'-F, 3'-F, 2'-Cl, 2'-Br and 2'-CF3 remarkably enhanced the activity. Generally, for the isomers with the same substituents at different positions, the order of the activity was ortho > meta > para. It was concluded that the target compounds represent a class of novel promising candidates or lead compounds for the development of new tetrahydroisoquinoline acaricidal agents.
    Molecules (Basel, Switzerland). 01/2014; 19(6):8051-8066.
  • Catalysis Communications 01/2014; 53:87–90. · 2.92 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 2-Aryl-3,4-dihydroisoquinolin-2-iums might be considered as a class of simple analogues of natural quaternary benzo[c]phenanthridine alkaloids. In this paper, 26 new 2-aryl-6,7-methylenedioxy-3,4-dihydroisoquinolin-2-ium bromides with various substituents in N-aromatic ring were synthesized from commercially available 1,3-benzodioxole in good to excellent yields. All the compounds were elucidated by MS, HRMS, IR, (1)H- and (13)C-NMR analysis, and evaluated for antifungal activities in vitro against Alternaria alternate, Curvularia lunata and Fusarium oxysporum sp. niveum at 50 µg/mL. Most of the compounds showed higher activities against all the test fungi than their natural model compounds sanguinarine and chelerythrine. For A. alternate and Curvularia lunata, most of them were also more active than thiabendazole, a commercial fungicide standard. The structure-activity relationship indicated that the substituent in N-aromatic ring and its position had significant effect on the activity. The general trend was that halogen atoms and CF3 remarkably enhanced the activity while CH3 and OCH3 decreased the activity. Generally, o-substituted isomers were more active than m- and p-substituted isomer. The present results suggest that the title compounds are potential for the development of new isoquinoline antimicrobial agents.
    Chemical & pharmaceutical bulletin 05/2013; · 1.70 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Four new coordination polymers, [Co(ppmdc)(H2O)2]n (1), [Ni(ppmdc)(H2O)2]n (2), [Mn(ppmdc)(H2O)]n (3) and {[Zn(ppmdc)(H2O)2]·H2O}n (4) (H2ppmdc = 2-(pyridin-4-yl)-4,6-pyrimidine dicarboxylic acid), have been synthesized by self-assembly of the newly designed H2ppmdc ligand and corresponding metal salts under hydrothermal conditions. The four complexes exhibit versatile frameworks with different topologies due to the different metal ions and especially the diverse coordination modes of the H2ppmdc ligand. Complexes 1 and 2 exhibit 2-D layered structures with (4·82)2 and (82)2 topology, respectively, which are constructed from the self-assembly of the L- and R-type single chain helixes, in which the ppmdc2− ligand adopts a μ3-kN,O:kN′:kO′ mode to link metal ions. Complex 3 features a 3-D metal–organic framework with 5-connected (45·65)2 topology, in which the metal ions are bridged by μ5-ppmdc2− ligands. Complex 4 possesses a 2-D sheet structure with 3-connected (63)2 topology, in which the ppmdc2− ligand adopts a μ3-kN:kO:kO′ mode to link Zn(II) ions. The thermal properties of complexes 1–4, and the magnetic property of 3 have been investigated and discussed in detail.
    CrystEngComm 04/2013; 15(20):4107-4116. · 3.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The title compounds are a class of structurally simple analogues of quaternary benzo[c]phenanthridine alkaloids (QBAs). In order to develop novel QBA-like antifungal drugs, in this study, 24 of the title compounds with various substituents on the N-phenyl ring were evaluated for bioactivity against seven phytopathogenic fungi using the mycelial growth rate method and their SAR discussed. Almost all the compounds showed definite activities in vitro against each of the test fungi at 50 μg/mL and a broad antifungal spectrum. In most cases, the mono-halogenated compounds 2-12 exhibited excellent activities superior to the QBAs sanguinarine and chelerythrine. Compound 8 possessed the strongest activities on each of the fungi with EC50 values of 8.88-19.88 µg/mL and a significant concentration-dependent relationship. The SAR is as follows: the N-phenyl group is a high sensitive structural moiety for the activity and the characteristics and position of substituents intensively influence the activity. Generally, electron-withdrawing substituents remarkably enhance the activity while electron-donating substituents cause a decrease of the activity. In most cases, ortha- and para-halogenated isomers were more active than the corresponding m-halogenated isomers. Thus, the title compounds emerged as promising lead compounds for the development of novel biomimetic antifungal agrochemicals. Compounds 8 and 2 should have great potential as new broad spectrum antifungal agents for plant protection.
    Molecules 01/2013; 18(9):10413-10424. · 2.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 1,3-Diiodotetrafluorobenzene and 1,3,5-trifluoro-2,4,6-triiodobenzene form co-crystals with 4,4′,6,6′-tetramethyl-2,2′-bipyrimidine, 1,2,4,5-tetra(3-pyridyl)benzene and 1,2,4,5-tetra(4-pyridyl)benzene in which the structural competition between ππ interactions and halogen bonds is directly observed. It is found that the strong C–IN halogen bond competes successfully with the ππ interaction between two 1,3-diiodotetrafluorobenzene molecules while the ππ interaction between two 1,3,5-trifluoro-2,4,6-triiodobenzene molecules can successfully compete with the strong C–IN halogen bond. Quantum chemical calculations explain the structural competition well.
    CrystEngComm 12/2012; 15(4):769-774. · 3.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: By employing sanguinarine, a natural active quaternary isoquinoline alkaloid, as a model molecule, a series of structurally simple quaternary 2-aryl-3,4-dihydroisoquinolin-2-ium compounds were designed and synthesized and evaluated for in vitro acaricidal activity against P. cuniculi. A new approach towards the title compounds was developed with isochroman as starting material. The results showed that 22 of 24 tested compounds displayed the activity in varying degrees at 0.4 mg/mL. Fourteen compounds were significantly more effective than ivermectin, a standard acaricide, and 6-methoxy dihydrosanguinarine, a derivative of sanguinarine (P < 0.05). And their comprehensive relative activity was 1.4 to 16.5 times than that of ivermectin and 1.5 to 18.8 times than that of 6-methoxy dihydrosanguinarine. The structure-activity relationship indicated that the introduction of a substituent to N-benzene ring, especially halogen atom and trifluoromethyl group, led to great improvement of the activity. The position of fluorine atom, methyl group and hydroxyl group made very significant effects on the activity. It was concluded that 2-aryl-3,4-dihydroisoquinolin-2-iums are very promising candidates for the development of new isoquinoline acaricidal agents.
    Chemical & pharmaceutical bulletin 12/2012; · 1.70 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: IN THE CRYSTAL STRUCTURE OF THE TITLE COMPOUND [SYSTEMATIC NAME: 6,7-dimeth-oxy-12-methyl-16,18-dioxa-12-aza-tetra-cyclo-[12.7.0.0(4,9).0(15,19)]henicosa-1(21),4,6,8,14,19-hexaen-3-ol], C(21)H(25)NO(5), the benzene rings exhibits a dihedral angle of 14.95 (4)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonding into inversion dimers. These dimers are further connected by C-H⋯O inter-actions.
    Acta Crystallographica Section E Structure Reports Online 06/2012; 68(Pt 6):o1762. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: IN THE TITLE COMPOUND (SYSTEMATIC NAME: 1,3-diiodo-4-meth-oxy-2-nitro-benzene), C(7)H(5)I(2)NO(3), the dihedral angle between the benzene ring and the nitro group is 88.0 (3)°, and the methyl group lies almost in the same plane as the ring [deviation = 0.034 (6) Å]. In the crystal, aromatic π-π stacking occurs between inversion-related rings [centroid-centroid separation = 3.865 (3) Å and slippage = 0.642 Å]. A possible weak C-I⋯π inter-action occurs [I⋯π = 3.701 (2) Å and C-I⋯π = 130.18 (13)°], but there are no significant inter-molecular I⋯I contacts.
    Acta Crystallographica Section E Structure Reports Online 05/2012; 68(Pt 5):o1500. · 0.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: AimTo investigate the total flavonoid contents and in vitro antioxidant activity of different extracts from Parnassia wightiana and their correlation.Methods50% ethanol (in water, V/V) extract from Parnassia wightiana W. was successively extracted by using 3 kinds of different solvents to provide chloroform extract (CE), ethyl acetate extract (EAE), n–butanol extract (BE) and water extract (WE). The content of flavonoids in each extract was determined using the NaNO2−Al(NO3)3-NaOH method. Different antioxidant assays (OH,· O2−,· DPPH · scavenging activity, reducing power and metal chelating activity) were employed to evaluate the antioxidant activities of four extracts, using butylated hydroxytoluene (BHT) as a reference.ResultsThe total flavonoid content in EAE was the highest, followed BE, WE and CE. WE and BE showed better antioxidant activity than CE and EAE. Each extract showed concentration dependent antioxidant activity and a high correlation between content of flavonoids and antioxidant activity.Conclusion The extrat of Parnassia wightiana W. may be used as natural antioxidant.
    Chinese Journal of Natural Medicines 05/2012; 10(3):190–195.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: IN THE TITLE COMPOUND [SYSTEMATIC NAME: 7,8-dimeth-oxy-11-methyl-17,19-dioxa-11-aza-tetra-cyclo-[12.7.0.0(4,9).0(16,20)]henicosa-1(21),4,6,8,14,16 (20)-hexaen-2-ol], C(21)H(25)NO(5), the benzene rings are inclined at a dihedral angle of 23.16 (5)°. One of the meth-oxy C atoms is close to coplanar with its attached ring [deviation = 0.129 (3) Å], whereas the other is orientated away from the ring [deviation = -1.124 (2) Å]. The 10-membered ring is highly puckered, and the OH and CH(3) substituents project to the same side of the ring. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into [010] chains and C-H⋯O and C-H⋯π inter-actions consolidate the packing.
    Acta Crystallographica Section E Structure Reports Online 01/2012; 68(Pt 1):o69. · 0.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In order to understand the antifungal activity of some derivatives of sanguinarine (S) and chelerythrine (C) and their structure-activity relationships, sixteen derivatives of S and C were prepared and evaluated for in vitro antifungal activity against seven phytopathogenic fungi by the mycelial growth rate method. The results showed that S, C and their 6-alkoxy dihydro derivatives S(1)-S(4), C(1)-C(4) and 6-cyanodihydro derivatives S(5), C(5) showed significant antifungal activity at 100 µg/mL against all the tested fungi. For most tested fungi, the median effective concentrations of S, S(1), C and C(1) were in a range of 14-50 µg/mL. The structure-activity relationship showed that the C=N+ moiety was the determinant for the antifungal activity of S and C. S(1)-S(5) and C(1)-C(5) could be considered as the precursors of S and C, respectively. Thus, the present results strongly suggested that S and C or their derivatives S(1)-S(5) and C(1)-C(5) should be considered as good lead compounds or model molecules to develop new anti-phytopathogenic fungal agents.
    Molecules 01/2012; 17(11):13026-35. · 2.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: From the ethyl acetate extract of the culture broth of Talaromyces verruculosus, a rhizosphere fungus of Stellera chamaejasme L., (−)-8-hydroxy-3-(4-hydroxypentyl)-3,4-dihydroisocoumarin (1) and (E)-3-(2,5-dioxo-3-(propan-2-ylidene)pyrrolidin-1-yl)acrylic acid (2) were isolated and evaluated for their antimicrobial activities. Their structures were elucidated by UV, IR, MS, 1H-NMR, 13C-NMR and 2D NMR spectra. Compound 1 exhibited the significant activities in vitro against two strains of bacteria and four strains of fungi. Compound 2 gave slight activities on the fungi at 100 µg mL−1, but no activities on the bacteria. Compound 1 should be considered as a new lead or model compound to develop new isocoumarin antimicrobial agents.
    Molecules 01/2012; 17(12):14091-8. · 2.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A highly regioselective isomerization-hydroaminomethylation of internal olefins has been developed. A 95.3% amine selectivity and 36.2 n/i ratio were obtained for 2-octene with a Tetrabi ligand and Rh(acac)(CO)(2), and a TON of linear amine was achieved of 6837 with a 39.1 n/i ratio of amine. The m-CF(3)-Ph substituted ligand was the best of the applied Tetrabi-type phosphorus ligands for different internal olefins, as up to a 99.2% amine selectivity and 95.6 n/i ratio were obtained for 2-pentene.
    Organic Letters 12/2011; 14(1):102-5. · 6.14 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: There are two independent mol-ecules in the asymmetric unit of the title compound, C(15)H(13)NO(2), in both the six-membered dihydro-pyridine rings adopt a half-chair conformation. The two benzene rings make dihedral angles of 43.66 (10) and 62.22 (10)° in the two mol-ecules. In the crystal, the two independent mol-ecules are linked alternately by inter-molecular O-H⋯O hydrogen bonds, forming a zigzag chain along the c axis. Furthermore, inter-molecular C-H⋯π inter-actions link the chains into a three-dimensional network.
    Acta Crystallographica Section E Structure Reports Online 10/2011; 67(Pt 10):o2721. · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In the title hemihydrated salt, C(15)H(13)BrN(+)·NCS(-)·0.5H(2)O, the two benzene rings are aligned at a dihedral angle of 46.9 (1)°. The six-membered heterocycle of the dihydro-isoquinoline unit adopts a half-chair conformation. The water mol-ecule and thio-cyanate ion are linked by O-H⋯N hydrogen bonds, generating a four-membered ring motif. In addition, C-H⋯O and C-H⋯S inter-actions link the components into a chain along the c axis. π-π inter-actions [centroid-centroid distance = 3.974 (2) Å] link the chains into sheets and further π-π [centroid-centroid distance = 3.746 (2) Å] and C-H⋯π inter-actions give rise to a three-dimensional nework.
    Acta Crystallographica Section E Structure Reports Online 10/2011; 67(Pt 10):o2766. · 0.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Study on the antibacterial activity of Viola yedoensis and the antibacterial active compounds. The chemical compositions were isolated by means of solvent extraction, column chromatography on silica gel, sephadex LH-20 and crystallization. The antibacterial activities were tested by Neo-Sensitab disk-diffusion method, nephelometric analysis and plating method. One new compound (4) along with three known compounds were isolated from this plant for the first time and were identified as aesculetin (1), 6,7-dimethoxycoumarin (2), scopoletin (3) and 5-methoxy-7-hydroxymethylcoumarin (4), respectively. All the compounds showed antibacterial and antibactericidal activities at varying degree on Streptococcus Aureas, S. agalactiae, S. uberis, S. dysgalactiae, E. coli and Salmonella, of which 1 was most active with 0.031- 0.313 g x L(-1) of minimal inhibitory concentrations (MIC) and 0.313 - 0.625 g x L(-1) of minimal bactericidal concentrations (MBC). Viola yedoensis has a broad spectrum of antibacterial activity on animal pathogenic bacteria, and coumarins may be the main antibacterial activity ingredients.
    Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 10/2011; 36(19):2666-71.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The title mol-ecule, C(18)H(16)O(3), contains three fused rings, of which the seven-membered cyclo-hept-2-enone ring has a screw-boat conformation. The two meth-oxy-phenyl rings make a dihedral angle of 50.4 (2)°. In the crystal, mol-ecules are linked by inter-molecular C-H⋯O hydrogen bonds, leading to a three-dimensional supra-molecular architecture.
    Acta Crystallographica Section E Structure Reports Online 09/2011; 67(Pt 9):o2282. · 0.35 Impact Factor

Publication Stats

33 Citations
96.89 Total Impact Points

Institutions

  • 2014
    • Northwest University
      Northwest Harborcreek, Pennsylvania, United States
  • 2011–2012
    • Northwest A & F University
      • • College of Life Sciences
      • • College of Science
      Yangling, Shaanxi Sheng, China
  • 2008–2009
    • Rutgers, The State University of New Jersey
      • Department of Chemical Biology
      New Brunswick, NJ, United States
  • 2007
    • Pennsylvania State University
      • Department of Chemistry
      University Park, MD, United States